Ships’ hulls,
surgical instruments and tennis racquets are just a few of
the ways in which a new steel (below) could
be used, said U.Va.
researchers Joe Poon (left), Gary
Shiflet (center) and Vijayabarathi Ponnambalam. The material
could be available for commercial use within three to five
years.

November
19, 2004

By Fariss Samarrai

The term “cross-disciplinary research” had not crossed
the minds of physicist Joe Poon or materials scientist Gary Shiflet
when they first met in 1985. They just realized they had a common
interest in “quasi crystals,” materials that have an
unusual atomic structure.

At that first meeting, Shiflet was holding an overdue library
textbook on phase transformation. Poon needed the book for
a class he was
teaching. They didn’t argue about it. Instead, they formed
a collaboration that has continued ever since, and now includes
other researchers from the College’s physics
department and
the materials science
department at the School of Engineering and
Applied Science.

“It was a natural fit for us to work together and share our knowledge
and equipment and resources,” Shiflet said, “that’s
why this collaboration has lasted so long.”

Besides, the two scientists like each other. “Our work has
been very productive,” Poon said.

No doubt. Throughout the years, Poon and Shiflet have won
several million dollars in grants for their investigations
into novel
materials. Early on, they received a grant from the Office
of the Vice Provost
for Research, who at the time was Gene Block. “That academic
enhancement grant from within the University kept us going before
the big government funding came,” Poon said.

As a result of years of collaborative work, the research
team has discovered a nonmagnetic amorphous material
that is three
times
stronger than conventional steel and has superior anticorrosion
properties.

A
future variation of this material, called DARVA-Glass 101, could
be used for making ship hulls,
lighter automobiles, tall buildings, corrosion-resistant
coatings,
surgical instruments
and recreational equipment. The scientists say commercial
use of the wear-resistant material could be available
within three
to
five years.

The material, made of steel alloys that possess a
randomized arrangement of atoms — thus “amorphous” steel — was
discovered by modifying an earlier version of amorphous steel
known as DARVA-Glass 1, first reported by Poon and Shiflet
at the Fall
2002 meeting of the Materials Research Society. This past
spring they reported on the more advanced DARVA-Glass 101
in the Journal
of Materials Research. A variety of popular newspapers and
magazines covered the discovery, including the Washington
Post, the Richmond
Times-Dispatch and the United Press International, and have
touted the material as the next big thing in steel. Scientific
American
magazine recently named Poon and Shiflet to its annual list
of the top 50 outstanding research leaders in science and
technology
for the year.

“Amorphous
steels can potentially revolutionize the steel industry,” Poon
said.
The Defense Department is particularly interested.
The project is sponsored by the Defense Advanced
Research Projects Agency,
the military’s research arm that supports investigations
into seemingly futuristic materials and technologies, but
with very real potential for applicability in the relatively
near future.

“They
have very high standards for success and progress and they are
mission-oriented,” Poon said.

According to Poon and Shiflet, researchers
have been making amorphous steel in very
small quantities
for
years, but
have had great
difficulty “scaling
up” the material to sizes large enough for practical use.
Poon and Shiflet have succeeded in producing large-size amorphous
steel samples that can be further scaled up in industrial labs
for mass production. They achieved this by adding a small dose
of a rare earth element — yttrium — to create
DARVA-Glass 101.

The “glass” in the material’s
name refers to the frozen liquid structure of the material, somewhat
similar to
glass that is a liquid made solid by rapid
cooling. But DARVA-Glass
101 is an aluminum-based metal composite
frozen to a solid state by rapid cooling.

The team is continually varying the recipe
for its materials by adding a pinch of
this element,
a dash
of that, and
by trying different
heating temperatures and cooling rates.
They are always tweaking the product, “trying to fool nature,” as Shiflet puts
it — always seeking to come up with something better
and stronger.

Most
of the lab work is done by co-investigator Vijayabarathi Ponnambalam,
a U.Va.
materials physicist. During
the last two years, the team
has produced more than 100 variations
of their
material on the journey toward the
creation of DARVA-Glass 101.

“The
problem with making a high-tech material is that, while nature
gives you something, it also takes
something away,” Shiflet
said. “We have been able to achieve great strength
and nonmagnetic properties for the material, but it is still
somewhat brittle.”

They
have a ways to go to achieve near
perfection.

“Discovery
is going on all the time,” Poon said. “We need to
toughen the material more. We can always make it better.”

But
discovery is not done randomly. The research team continually
revises its strategies
based on each new knowledge gained, and what
they think may
happen if they
try something
else — perhaps
something outrageous. They also use computer models to make rational guesses
about how a metal may respond to different temperatures or to the introduction
of new elements.

“Unlike
previous variations of amorphous steel, DARVA-Glass 101 can be
produced in sizable quantities, and it can be machined as well
as manipulated like a plastic. “It
can be squeezed, compressed, flattened and shaped.” Poon said.

The
material is of interest to the Navy for making nonmagnetic ship
hulls, particularly
for submarines,
which are detectable
by the magnetic
field
of their hulls. The
amorphous steel that the U.Va. team is
refining
also may be useful for producing lighter
but harder armor-piercing
projectiles.
The publicly traded company
Liquidmetal Technologies owns an exclusive
license to the
amorphous steel
invented by the
U.Va. scientists.